For your setup you will need to manually configure the connection. There is a good document on the wiki for setting up a sipura device so it will utilize the features of LMCE using a bit of a hack, but it does work. Now, the only part of that guide that will really be useful to you is the hack, you need to do it this way it you want to utilize the features of LMCE, otherwise you will only be making/receiving calls and not much else will work for you.
Do NOT edit the config files manually as FreePBX will overwrite your changes. There are a few files you can tweak without being overwritten, but trust me when I tell you to do it through the FreePBX pages.
If you have specific questions regarding the setup I have done a fair bit of playing with different telecom options and can probably assist if needed, but read through the wiki page on the Sipura and I think you'll be fine on your own.
As always, if you get the device working properly, please contribute back and document the steps taken and post them to the wiki so other people can reference them going forward.